Category: Epidemiology

Photo used with permission from the Liz Ehlinger Archives, all rights reserved.

Pandemics are in the news again with two recent outbreaks beginning to cause alarm. How much danger do modern pandemics actually pose to the international community? Should Americans be concerned about a serious pandemic?

To answer these questions, we first need to introduce some history.

The Modern Pandemic

In November 2002 SARS (Severe Acute Respiratory Syndrome), a coronavirus originating near Hong Kong, began to be recognized as a serious threat and a potential pandemic. By March 2003, the international public health community was taking strong measures to contain the highly contagious disease. By the time the virus was under control in 2004, 8096 people had been infected and 774 had died, giving a mortality rate of 9.6%.

In 2009, a novel form of H1N1 began to spread in the US and Mexico. This subtype of Influenza A virus was also responsible for the devastating 1918 “Spanish Flu” pandemic. Public health officials had been preparing for an outbreak of H5N1 and so had good procedures in place for an influenza outbreak, but were not prepared with specific countermeasures for H1N1. It is much more difficult to estimate the scope and mortality rate of this disease than the SARS outbreak because of its resemblance to more common influenza infections, which are very common. According to a 2012 statistical analysis, approximately 201,200 people died of H1N1 from 2009-2010.

Currently in the news: a SARS-like virus, MERS, is proliferating in the Middle East and a new influenza subtype, H7N9, is beginning to cause concern. At an annual World Health Organization (WHO) meeting in Switzerland Monday the WHO director called MERS a “threat to the entire world” and her “greatest priority.”

So what level of effort and concern should the average person invest in these threats? What can medical professionals do to keep up with the latest outbreaks? Let’s try to sort through the responses to an epidemic.

Epidemiology

When potential pandemics arise, the WHO tracks outbreaks of these illnesses carefully and prepares an international response. In the United States, the CDC directs these efforts along with state and local public health infrastructure.

The CDC has a Health Alert Network which will email subscribers with updates on health events. It is open to everyone, though they describe this as their “primary method of sharing cleared information about urgent public health incidents with public information officers; federal, state, territorial, and local public health practitioners; clinicians; and public health laboratories.” The WHO in turn has their Disease Outbreak News feed to keep people informed of epidemic threats.

The key to epidemiology is early containment, and communication is an essential part of that. The battle against H1N1 was bolstered by a strong vaccination program, and SARS was contained with a massive public health effort which included widespread quarantines and even pre-departure screenings. But the front line of containment is letting doctors (and patients) know what symptoms to look for so that patients can be isolated and proper precautions taken.

We talked to Dr. David Hooper of Massachusetts General Hospital (MGH) about how the hospital ensures proper information is disseminated. Aside from research that doctors in the hospital may do on their own, Hooper and his colleague Paul Biddinger in the Emergency Department continually monitor email notifications from local, state, national, and international health authorities. “If an alert came in, we would make sure some version of it was disseminated to relevant staff,” he said.

Occasionally they are contacted directly for local issues but overwhelmingly this method depends on the diligence of doctors. “All of us are tied into email pretty much constantly with our smartphones and laptops,” Hooper said.

We also talked to a Connecticut physician in a smaller practice, Dr. Hugh Blumenfeld. He relies exclusively on CDC alert emails to keep up to date on epidemic warnings.

In the recent past, these methods of communication seem to have been successful. While The Spanish Flu of 1918 claimed the lives of about 50 million people, and infected about 20% of the world’s population, we haven’t experienced a pandemic of nearly that proportion since then.

Media Response

The media tends to present stories in a way that will sell, and in the case of epidemics this means exaggerating the risk. But in this case, exaggeration is not necessarily a bad thing.

In reality, your chances of dying as part of a pandemic are quite low. During the SARS outbreak, 92% of the recorded infections were in China. Given the media storm, you might be surprised to know that not a single death from SARS was recorded in the US. Even H1N1 was not in danger of being as deadly as cancer in 2009.

But unlike cancer, pandemics are an unknown risk. We never know when some newly mutated high-mortality virus could run out of control. Because of this, we are best served treating every outbreak as if it could be disastrous (at least in terms of communication). Global travel has upped the ante in terms of how fast these diseases can spread, and we need to be well-informed and prepared to act quickly.

New Frontiers

While the new era of global travel complicates disease control, scientific research on pandemic prevention is becoming more complicated as well. A recent JAMA article on H7N9 preparedness concludes:

Another influenza pandemic is inevitable. Even with recent additional vaccine manufacturing capacity and improvements in potency testing, the global public health community remains woefully underprepared for an effective vaccine response to a pandemic. To be successful in meeting the challenge of a severe pandemic, the influenza vaccine enterprise must move forward with the development of novel antigen influenza vaccines that protect most individuals from multiple strains of influenza.

And even the development of these vaccines has become a contentious issue. The Dutch lab that identified the MERS virus recently filed a patent on some applications of the virus such as the creation of a vaccine. This may make it impossible for anyone to manufacture a vaccine for MERS without their permission. The lab insists that this will cause pharmaceutical companies to show more interest in creating a vaccine.

In order to be effective, these vaccines must be very widely distributed very quickly. If only one company can produce a vaccine for a particular virus, there must be a way to ensure that they can deliver large amounts in a timely fashion, and that there won’t be price gouging which makes it impossible to afford in the proper quantities. The WHO is currently investigating this issue.

So, should you be worried about pandemics? Not yet, but you should keep your eye on them. If you follow the scope and severity of outbreaks, you will know when it’s time to worry.